Description
A multipoint feature is a single feature composed of many individual points and is generally used to manage very large collections of point data. Each multipoint feature is represented as one record in the attribute table.
This type of data is not supported by this tool because a valid output cannot be provided for each of the individual elements.
Solution
Use the Multipart To Singlepart tool in the Data management toolset to convert the multipoint data into a regular point data, which can then be used as input to the tool.